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-   -   replacing rod with 1*19 wire (http://www.briontoss.com/spartalk/showthread.php?t=68)

Bryanj 09-16-2005 08:33 PM

replacing rod with 1*19 wire
 
What is the cost differential between rod and wire?

Can rod be replaced by wire?

If so how do you make mast connections?

Is matching strength or stretch more important (rod versus wire)?

Will termination pins match (i.e. if the cap shroud ends on deck with a 1/2" pin would the 1*19 wire turnbuckle also use a 1/2" pin even though the wire has a larger diameter than the rod?)

Thanks,

Bryan

TomP 09-17-2005 10:28 AM

Rod to Wire
 
Yes, you can replace rod with wire. But it is not really that easy. There are many things to consider and they add up quickly, both in cost and wieght.
Here is a partial example of a re-rig on a 1981 C&C 36 IOR that we recently completed.
Backstay. lenght 51 feet.
Nitronic 50 -12 7mm dia, 12,500 break, .21lbs/ft, $7.00/ft
1x19 Wire 3/8 10mm dia, 16,000 break, .30lbs/ft, $3.50/ft
Dyform 1x19 8mm dia, 13,500 break, .23lbs/ft, $4.90/ft

This is just the wire, you must consider the attachment points (terminals, turnbuckles, etc). Typically the termination pins will not match, for 3/8 wire you could use a 5/8 or 3/4 stud, the corresponding turnbuckle would have the same pin (5/8 or 3/4). Dyform gets you close using 8mm you can use a 5/16 terminal which is available in 1/2 or 5/8. IF there is sufficient meat on the chainplate, it MAY be possible to drill the hole to 5/8.
You must consdier the weight when doing something like this. You must examine the affect of the weight aloft will have on the righting moment of th yacht. In the example the rod weighs about 11 pounds, the wire is 15 pounds, and the Dyform is about 12 pounds. The four pound difference between rod and 1x19 may not seem significant, but add the associated terminals and the rest of the rig you could be swinging an extra 60 or more pounds aloft. It could make an otherwise stable boat into a rocking chair, not to mention the safety factors. Get a copy of "The Apprentice", "Skene's Elements", and if you really want to hurt your head, Marchaj "Aero-Hydrodynamics of Sailing" and study righting moments and rig design, find a knowledgeable rigger who has done similar work.

Strength is always more important.

Hope this helps in some foundation.

Bryanj 09-19-2005 08:03 PM

Thanks Tom!

Everything is a trade off so it seems like it is worth asking a general question like this. It does not sound like the material cost savings are enough to offset replacing terminal fittings and all the other changes that need to be made.

So I guess the next question is can rod be shopped? Is the price the same regardless of who does the work? It's all Navtec.

Bryan

TomP 09-23-2005 10:17 AM

Shopping Rod
 
Bryan,

You can try shopping rod, but I think you might find that if a rod worker has it cheaper than where you are you are going to pay the difference in shipping. Rod cannot be coiled like 1x19 or dyform without hurting it. The last rod we re-headed had to be coiled in a 6 foot diameter for shipping...just a little over size for fed ex or ups so it had to go by truck. Roughly three times the cost.

Good luck,

Tom

Bryanj 09-27-2005 07:07 PM

Thanks Tom,

Sounds the local guys are the way to go.

Bryan

lfreeman 03-17-2008 12:02 PM

I'm thinking about making an offer on an esprit 37 with rod rigging. The discussion of rod versus wire earlier in this thread was useful.

Don't know the age of the rigging on this particular boat, or it's inspection history so I would want to have a complete inspection done. and probably re-head the rods (at a minimum). I want to consider the possibility of a complete rerig when I make the offer.

Question is, how much of the length of the rod gets used up in re-heading and are longer screws for the Navtec screw-type turnbuckles available to make up for loss of length of the rod?

Thanks, Larry


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